Branchable can now use Lets Encrypt to get https certificates.
We plan to eventually use this for all sites hosted at Branchable, but if you'd like to help test it with your site, you can now. Just go to the Control Panel, click on the Setup button for your site, check the box for "use Lets Encrypt to generate http certificate", and save the change.
It may take a day or two for your site to get a certificate from Lets Encrypt, depending on how many others are requesting a certificate. Once your site gets a Lets Encrypt certificate, it should be renewed every 90 days automatically from then on.